Aim: This study was performed to evaluate fluoride uptake by sound enamel after using Iranian Schools' NaF mouthrinse in comparison with an ADA approved rinse (NaFRINSE) as a standard caries inhibition product in vitro.

Method & Materials: In this experimental study, 30 extracted human sound premolars were randomly divided into two groups of 15 and each tooth was longitudinally bisected into experimental and control halves. A specified hemi circular area on each experimental half was treated with one of the rinses. Two subsequent biopsies were taken from each half using Acid Etch Enamel Biopsy technique. Fluoride and calcium contents of each half were then measured in order to evaluate fluoride uptake and biopsy depth, respectively.

Results: After calculations and statistical analysis using Repeated Measure method it was shown that, enamel fluoride content increases after use of both rinses in the two depths. 594.55 and 463.33 ppm for the first and second enamel layers in Iranian mouthrinse and 781.41 and 488.73 for NaFRINSE respectively. Difference between the uptakes from the two rinses is not significantly different.

Conclusion: It was concluded that the Iranian mouthrinse is capable of increasing fluoride content of tooth enamel as much as the American standard one and thus, its use is advised, as a complement for the daily brushing program, especially for the areas in which caries prevalence is high.